They allow you to plug 3 power cords into a single grounded outlet. What more can you say. They work great and the price is right. Those things should always be plugged directly into an outlet. If you're not sure about a specific application be sure to ask an electrician.
eBay
Material: Panel (pure copper), bottom box (alloy). At the end of the panel, cover the ferrule and fix it with screws and ferrule. Weight: 392g.
eBay
USB Charging Range : Phone, Pad, Pod, PDA, MP3 etc. The USB charging protection function also can protect your devices. for back and side wiring. Include screw and one wall plate. USB Output : DC 5V 2.1A.
eBay
This is for a New Eaton Crouse-Hinds APJ6375 model M4 60 Amp Plug. The plug is new and comes in the original box. The original box is not in perfect condition and has been opened and inspected. #ZE201
eBay
Adjustable AU/US Plug 1To3 Wall 2Pin US Socket Outlet Converter Adapter With Switch For Electric Fan Sleep Breeze. 1To3 Converter Triple Wall 2Pin US Socket Outlet. or avoid even the minimum wind gear when the wind exceeds the body comfort level when sleeping.
eBay
IEC Socket. RCA Socket. HiFi Power Cable. US Power Plug. HiFi Power Plug. 4Layer Plated: Oxygen Free Copper-Plated >>>> Silver-Plated >>>> Palladium-Plated >>>> Gold-Plated. UK Power Plug. EU Power Plug.
eBay
GFCI Test: ＞5mA (US Plug). Electric Socket Tester - Advanced socket tester for rapidly detecting whether the socket's wire connection is correct or not. Bright LED Light & 3 Test Indicators - The light patterns are well labeled on the surface of the socket tester.
eBay
Improve Energy Efficiency: After installation, the wall switch socket cover can seal the vents tightly, making it difficult for cold air/warm air to escape through the air outlet box, which can effectively prevent wind and heat insulation and help improve energy.
eBay